A diver is silhouetted against the sunlit surface as hundreds of
schooling baitfish cluster around a large outcropping of black coral. At
about one inch of growth per year, black coral is one of the slowest
growing corals on the reef. Once thought to have the power to cure
disease, the polished ebony skeleton of this variantly-colored family of corals is used to make jewelry in
many parts of the world. In the US state of Hawaii, for example, it is
unfortunately designated as the
state
gem [Waikiki aquarium PDF file], a controversial label which can only help
contribute to its scarcity. Fortunately for its survival, black coral thrives
at depths
over 100 feet-- considered deep by sport divers, though advances in dive
technology are diminishing this natural obstacle to black coral
collection (as noted in the Honolulu
Star-Bulletin). Black corals
belong to order Antipatharia, which literally means "against
disease".